All the filters offered for Harley's have become overpriced, probably because the companies selling them use the overpriced OEM product as a pricing baseline. As mentioned above, look for them on sale the same way many of us do when buying oil.
Harley used to claim their filter was 10 micron, then magically they changed the print on the box and it became a 5 micron filter. As best I can tell, it's still the same filter. People get caught up in advertising hype and BS, instead of actually studying how these things are actually rated. Just be aware that some of the beneficial stuff in motor oil is larger than 5 microns in size, then think about that 5 micron filter claim.
Jerry
btw, for those who don't know, 1 micron = 0.00004", so 5 microns would be 0.00020 inches.